1. Field of the Invention
The present invention generally relates to an improved structural system. More particularly, the present invention relates to a unique structural system that optimally balances compressive and tensile forces to produce strong, resilient structures using a minimum of material.
2. Brief Description of the Related Art
The first geodesic dome, a highly sub-divided icosahedron, with great circle arcs, was built in 1922 by Dr. Walter Bauersfeld. The structure was built on the roof of the Carl Zeiss optical works in Jena, Germany, and served as the first planetarium projector. The geodesic dome as a form of architecture was popularized by Richard Buckminster Fuller in the early 1950s. Fuller experimented with the interplay between compression and tensile forces in structures, and coined the term xe2x80x9ctensegrity.xe2x80x9d
The word xe2x80x98tensegrityxe2x80x99 is an invention: a contraction of xe2x80x98tensional integrity.xe2x80x99 Tensegrity describes a structural-relationship principle in which structural shape is guaranteed by the finitely closed, comprehensively continuous, tensional behaviors of the system and not by the discontinuous and exclusively local compressional member behaviors. Tensegrity provides the ability to yield increasingly without ultimately breaking or coming asunder.
Many types of structures are known in the art that employ the principles of geodesics and tensegrity. Matan et al., in U.S. Pat. No. 5,688,604, disclose a deformable, resilient tensegrity structure, wherein elastic tensile cords connect compression struts, with the tip of each strut being connected to the center of another.
Huegy, in U.S. Pat. No. 4,901,483, discloses a geodesic dome type tensegrity structure based on the helix formula and exhibiting features that enable easy construction.
Castro, in U.S. Pat. No. 5,857,294, discloses a dome roof support system of any arbitrary closed perimeter shape, wherein trusses are supported by a series of strategically placed vertebral compression members.
Several problems remain inherent in conventional structural design, most notably in geodesic and tensegrity design, which have stopped their usefulness as a system to model natural structuring, as well as limited their development as a widely deployed building system. These problems originated in early tensegrity theorizing with the insistence that compression be treated as linear, axial, chordal, discontinuous, and islanded in a xe2x80x98sea of tension.xe2x80x99
Geodesic design axiomatically insists that compressive members be treated as linear and isolated, and that even a pneumatic structure such as a spherical manifold is optimally resolved into discrete patterns of tension and compression by a curved truss of sticks and knobs (struts and joints thereof). Limits to popular use of geodesics and tensegrities are soon apparent as increasingly large simple shapes require ever more complex, numerous, and consistently accurate components.
It is thus one object of the present invention to provide a structural system wherein compressive and tensile forces are optimally balanced in dynamic equilibrium.
It is a further goal of the present invention to provide a structurally independent building system, obviating the need for a foundation.
Yet another goal of the present invention is to provide a structure immune to catastrophic failure. The structures of the present invention can absorb dynamic loads that would flatten or fold traditional dome structures.
Still a further goal of the present invention is to provide a simple and inexpensive structure, lightweight and compact for storage and portage which is expandable and modular structure capable of being erected in a short time with a minimum of manpower, erection tools, or other facilities and structures.
A still further goal of the present invention is to provide a structural system wherein the delivery of utilities, such as heated/cooled air, water, electricity, data and information conduits, etc., is performed by integration of passageways for these utilities with the structural elements of the edifice.
Yet another goal of the present invention is to provide a structural/dynamic modeling framework, unlimited in application and scalable through all levels from quantum to universal.
The term SYNETIC is defined as the essential feature of a new building system where discrete patterns of compression optimally co-function with discrete patterns of tension to form structures in dynamic equilibrium. Synetic design utilizes minimal tensile and minimal compressive material. Synetic structures are pneumatic in behavior, the resolution of a manifold into optimally minimal and discrete co-functioning patterns of tension and compression. Energetic behaviors, deriving only from topology, and which operate at all scales, form and inform Synetic structure.
The present invention relates to a system of construction that utilizes the compressive properties of structural materials to the fullest advantage. In general, the invention is useful wherever it is advantageous to make the largest and strongest structure per pound of structural material employed. The invention relates to a structural system that may be employed in a wide variety of structures, including but not limited to domes, spheres, toroids and other pneumatic shapes useful as buildings. The invention also relates to a tension-compression modeling system used to teach and explore principles of dynamic forces that might apply to intangible and invisible structures.
The present invention relates to the discovery of a means and methodology to further reduce the aspect of compression in a structure so that, to a greater extent than has heretofore been possible, the structure will have the aspect of continuous compression throughout and the tension will be subjugated so that the tension elements become involved variously and as required to brace, support and pre-stress the compression net. In some embodiments tension functions are discontinuous, invisible, and the compressive aspects dominant throughout. One illustrative exercise helpful to understanding the present invention is to imagine taking the compressive force out of the single column or spar of a tent or tensegrity structure and, through the creation of a structure having continuous and finely divided compression, spreading the compressive function relatively evenly throughout the manifold.
The structure and operation of the present invention may be better understood by considering in turn the elements of Synetic structures: compression, tension, and attachment.
Synetic Compression
Synetic compression elements are curved, continuous, wavilinear and cyclical in nature. They are non great-circular and non-equatorial, i.e., they are non-geodesic, but they are everywhere ideally braced by geodesic tension. Conversely, Synetic compression, at all points, ideally braces geodesic tensile patterns.
In one embodiment of the present invention, compressive material is stiff, springy rod or tube (or bundles of rods or tubes) bent into arcs. Arcs are joined to form curved domical spans of a diameter many times that of an individual arc and very many times greater than the rod or bundle diameter. Frames use the minimum possible compressive material. Large structures have little air resistance and very little opacity.
Particularly important Synetic compressive elements are hoops of appropriate material, which have strong tendencies toward circularity, flatness, and a larger radius. Hoop-strength becomes sphere-strength.
Synetic Tension
Synetic tension is minimum, discontinuous, axial, chordal, straight, and geodesic.
Synetic frames are structurally independent of covering, and therefore may be wrapped, perhaps with material too weak to be used in conventional tents and domes. Being curvilinear throughout, they are particularly accommodating to thin material, fabric, nets and membranes. The structural independence of a Synetic frame allows covers to be made using simple gores and patterns relatively unrelated to the dome geometry. They support material that is too weak for conventional construction that may be layered, overlapped, wrapped. The radially expansive nature of Synetic frames allows such material to be maintained easily in uniform tension overall, providing smooth, structurally rational surfaces for further rigidifying. Uniform tension in the membrane diminishes flapping and mechanical degradation, reduces air resistance, sheds detritus, and pre-stresses the compression net. Although structurally independent, Synetic frames may be greatly strengthened by tensile attachment. Tensile bracing might be only a minimum required to maintain the balanced array of bows and accomplished by inter-linking arcs, or by tying or lashing of points of crossing or of tangency.
Further strengthening of a Synetic frame is derived from incremental addition of circumferentially comprehensive tension portions in the form of lines, nets, or fabric, until the frame is maximally braced in full membrane stress. The most efficient tensile patterns bracing Synetic structure will be geodesic.
Synetic Attachment
Synetic attachment is entirely by tangency, the universal cohesive principle of natural structuring. Tangent connection is thoroughly structurally integral, distributing dynamic loads throughout a Synetic structure with maximum efficiency. Synetic vertices are woven, turbined, and empty. Tangent connections are in pure thrust; they could comprise for example conventional compression fittings with continuous cable or strapping, or adhesive, welded or chemically bonded joints may be employed. Folding or collapsing of the structures may be accomplished by shortening or lengthening the compressive members in concert with corresponding adjustments to lengths of tensile material. Hinges or nodes might be included in compressive material to facilitate folding or erection of Synetic structures. Certain tension stays also might be easily demountable to aid folding and erection.
Synetic compressive elements are tangent to the whole, tangent locally to each other, join whole or partial structures, regular or irregular, globally or locally, larger to smaller, high frequency to low, one symmetry to another, planar to curved structure, concave to convex, angular to smooth, tension to compression, radial to tangential, rigid to flexible.
While Synetics shows integral waveforms, or curves of least work symmetrically impounded on a sphere, it also shows valency, potential connectivity that is symmetrically disposed by the same dynamic. Polygonal Synetic modular units and sub-assemblies are comprised of individual bowed arcs, paired arcs, or triangles of arcs, or modular units may be comprised of five-, six-, seven-, or eight-fold stars of incurved arcs, or they may be comprised of circles or other closed, cyclic patterns of arcs. The use of longer paths could allow certain constructions to be made of material directly from a coil by methods analogous to knitting. Polyhedral modular units are balanced symmetric arrays of inwardly curved arcs corresponding to the edges of tetrahedra, octahedra and icosahedra and consequently to all lattices, compounds and tesselations of them.
Synetic Models
Synetic design provides simple, self-similar, uniform structure, rendered in energetic, self-adjusting terms, well suited to symmetric development and polyhedral elaboration. Synetic flexibility allows open arrays, cages, and higher globally symmetric breakdowns or structure of negative curvature, all rendered in synergetic terms.
Synetics models the dynamics of structure in minimal terms of angle and energy.
At the quantum level of modeling, Synetics provide waveform, cyclic, integral curves of least work symmetrically impounded in open or closed systems.
At the atomic level, Synetic tangent articulation represents sites of valency, symmetrically disposed by balanced bowed arcs that are self-coordinating in structure of any complexity.
The energetics of atomic clusters may be realistically modeled without recourse to the numerology of close-packed spheres or cannonballs. Conventional ball-and-stick atomic modeling obscures the nature of attachment by positing spherical and cylindrical entities where only considerations of angle and frequency are appropriate.
While Synetics accommodates all regular lattices, its flexibility allows construction of open arrays, cages, zeolites, as well as structure with complex or negative curvature, toroids, helical tubes, etc. For example, Synetic tetrahedra model carbon structure, graphene sheets, triply periodic sponges, fullerenes, tubes, horns, helices and so forth. Similarly, it models tetrahedonal silicate elaborations.
On the scale of the architecture of life, Synetics models the tangent relations between fibers and membranes, fiber and fiber, conforming to minutely accretive structure as well as to branching, tree-like growth. Synetics also conforms to the interstitial architecture of minimal tension surfaces, relations between membrane and membrane, of cells, bubbles and foam.